90 - (2^2.25 - 3^2 . 7)
a,-3/5.2/7+-3/7.3/5+-3/7
b,6^4.3^2.25^2-8^3.9^2.125/5^2.4^3.3^4
a,-3/5.2/7+-3/7.3/5+-3/7
=-3/7.2/5+(-3/7).3/5+(-3/7)
=-3/7(2/5+3/5+1)
=-3/7.2
=-6/7
\(\frac{-3}{5}\)và\(\frac{2}{7}\)mình đổi hai mẫu cho nhau
Câu 1: Tính
a: 3/7+8/7, b: (3/2)^2, c:4^2.25^2, d:84^2/21^2,
e:A= 1/4.11/7+17/28-0,5
Câu 2: Tìm x, biết x/3=-3/9
các bạn giúp mik với. cảm ơn các bạn trước
Câu 1 Thực hiện phép tính
a) 3^3 +3^2 - (2^7 : 2^5 + 7^8 : 7^7)
b) 27.77 + 27.27 - 27
c) 52 : (43-30) + 144 - 16
d) 174 : {2[36 + (4^2 - 23)]}
e) 180 : {300 : [450 - (4.5^3 - 2^2.25)]}
f) 3^2.101 - 3^2.101^0
( Dấu "^" là dấu mũ nha )
\(a,3^3+3^2-\left(2^7:2^5+7^8:7^7\right)=27+9-\left(2^2+7\right)=36-11=25\)
\(b,27.77+27.27-27=27\left(77+27-1\right)=27.103=2781\)
\(c,52:\left(43-30\right)+144-16=52:13+128=4+128=132\)
\(f,3^2.101-3^2.101^0=3^2\left(101-101^0\right)=9\left(101-1\right)=9.100=900\)
a.=27+9-(2^2+7^1) =36-(4+7) =36-11 =25
33+32-(27:25+78:77)
=27+9-(22+7)
=36-(4+7)
=36-11
=25
b.bạn tự lm nha
c.52:(43-30)+144-16
=52:13+144-16
=4+144-16
=148-16
=132
d.174:{2[36+(42-23)]}
=174:{2[36+(16-23)]}
=174:{2[36+-7]}
=174:{2.29}
=174:58
=3
2 1/3 + ( - 0.25 ) + 3/8 -2.25 + 1/2 + 5.1
2.25 x 0.5 + 2.25 : 2 + 3.75
=2.25*\(\left(0.5+2\right)\)+3.75
=2.25*2.5+3.75
=5.625+3.75
=5.7
180:{300:[450-(4.5^3-2^2.25)]}
\(180:\left\{300:\left[450-\left(4.5^3-2^2.25\right)\right]\right\}\\ =180:\left\{300:\left[450-\left(4.125-4.25\right)\right]\right\}\\ =180:\left\{300:\left[450-\left(500-100\right)\right]\right\}\\ =180:\left\{300:\left[450-400\right]\right\}\\ =180:\left\{300:50\right\}\\ =180:6\\ =30\)
\(180:\left\{300:\left[450-\left(4.5^3-2^2.25\right)\right]\right\}\\ =180:\left\{300:\left[450-\left(4.125-4.25\right)\right]\right\}\\ =180:\left\{300:\left[450-\left(4.100\right)\right]\right\}\\ =180:\left\{300:\left[450-400\right]\right\}\\ =180:\left\{300:50\right\}\\ =180:6\\ =30\)
Thực hiện phép tính( tính nhanh nếu có thể):
a/ 26 + 173 + 74 + 27
b/ 75.37 + 89.46 + 75.52 - 89.21
c/ \(2^7:2^2+5^4:5^3.2^4-3.2^5\)
d/ \(100:\left\{250:\left[450-\left(4.5^3-2^2.25\right)\right]\right\}\)
a) \(26+173+74+27\)
\(=\left(26+74\right)+\left(173+27\right)\)
\(=100+200\)
\(=300\)
b) \(75\cdot37+89\cdot46+75\cdot52-89\cdot21\)
\(=75\cdot\left(37+52\right)+89\cdot\left(46-21\right)\)
\(=75\cdot89+89\cdot25\)
\(=89\cdot\left(75+25\right)\)
\(=89\cdot100\)
\(=8900\)
c) \(2^7:2^2+5^4:5^3\cdot2^4-3\cdot2^5\)
\(=2^{7-2}+5^{4-3}\cdot2^4-3\cdot2^5\)
\(=2^5+5\cdot2^4-3\cdot2^5\)
\(=2^4\cdot\left(2+5-3\cdot2\right)\)
\(=2^4\cdot\left(7-6\right)\)
\(=2^4\)
\(=16\)
d) \(100:\left\{250:\left[450-\left(4\cdot5^3-2^2\cdot25\right)\right]\right\}\)
\(=100:\left\{250:\left[450-\left(4\cdot5^3-4\cdot5^2\right)\right]\right\}\)
\(=100:\left[250:\left(450-4\cdot5^2\cdot4\right)\right]\)
\(=100:\left[250:\left(450-400\right)\right]\)
\(=100:\left(250:50\right)\)
\(=100:5\)
\(=20\)
Tính hợp lý:
\(\dfrac{4^2.25^2+2^5.5^3}{2^{10}.11+2^{10}.5}\)
\(=\dfrac{2^4\cdot5^4+2^5\cdot5^3}{2^{10}\cdot16}=\dfrac{2^4\cdot5^3\left(5+2\right)}{2^{10}\cdot2^4}=\dfrac{2^4\cdot5^3\cdot7}{2^{14}}=\dfrac{5^3\cdot7}{2^{10}}=\dfrac{875}{1024}\)
tìm x thỏa mãn (3^3)^2+2^x = 5.(45+2^2.25)+8
(3^3)^2 + 2^x = 733
729 + 2^x = 733
2^x = 733 - 729
2^x = 4
Vậy x = 2
k cho mình nha